Recent Advances in Modification and Application of Polyhedral Oligomeric Silsesquioxane/Polyurethane Composites: A Comprehensive Review

Great challenges stand in the development of polyurethane (PU) due to its inherent flammability, suboptimal water resistance, and poor weather fastness. Polyhedral oligomeric silsesquioxane (POSS), acts as a classic nano-modifier with good biocompatibility, stability, non-toxicity, and easy-modification, also, widely used in various polymer fields. Introducing POSS into PU is a significant way to improve the defects and realize multifunctional modification. A brand-new comprehensive summary of POSS/PU materials over the past 5 years, including molecular characteristics, preparation methods, reaction mechanisms, intrinsic attributes, and practical applications, is presented in this manuscript. First, the structure and properties of PU and POSS are elucidated from the molecular perspective. Subsequently, the influence of POSS on the morphological structure, interfacial performance, mechanical attributes, and thermal properties of PU is systematically discussed, demonstrating the potential of POSS in improving novel PU materials. Finally, the research progress of POSS/PU composites in functional coatings, biomedical materials, flame-retardant materials, and solid energetic materials is emphatically introduced. Additionally, the review analyses a brief understanding of the challenges of POSS/PU composites in the research progress, and the following development directions are also prospected, providing an important reference for the production and applications of POSS/PU materials in the future.